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• You can use org.openide.util.WeakListeners in order to create event listeners that will be removed is the source isn't being used anymore. This minimses the chance of memory leaks (see book NB for Beginners) in case you cannot remove the registered listener. Typical use case: register LookupListener in the constructor of a ContextAware action.

• If you experience that the EDT is blocked shortly after you haven opened the first dialog, or at least shortly after application startup, then you should add -Dsun.awt.nopixfmt=true as VM option to the run configuration.
  The blocking is caused by a known bug in the JDK. Related Bug entries are:

  • [JDK-8019378] Win32GraphicsDevice.isPixFmtSupported[native]() extremely slow

  • [JDK-6477756] GraphicsDevice.getConfigurations() is slow taking 3 or more seconds

  • NetBeans Report #199452

Preferences

Don't use PropertyMap anymore, always use java.util.Preferences instead (SnapApp.getPreferences()), for compatibility during migration use org.esa.snap.gui.compat.CompatiblePropertyMap.

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